The use of barges or lighters to transport cargo is common in marine transportation. Barges may be used singly or in groups. The groups may be referred to as barge trains. A barge or a barge train may be towed by a tug boat or a powered vessel or pulled by other suitable means.
Barges are, commonly, rectangular in shape with a straight or square bow, although very large barges, particularly, those used in deep sea voyages or on the open ocean may have a shaped bow for better sea-keeping characteristics than a barge with a square bow.
The barges in a barge train carrying goods in harbors and along rivers are, usually, lashed tightly together, two or three abreast, with several successive rows of such barges in one barge train. Such barge trains are, usually, pushed by the tug boat, rather than being pulled by the tug boat.
In recent years a new method of using barges has been developed. A number of barges are loaded with cargo at various upriver ports or in various parts of a harbor. A barge train is then formed by securing together a mumber of barges. The barge train is then towed to an ocean-going ship lying in a harbor. The barge train is broken up and the barges are, individually, lifted aboard the ocean-going ship. Aboard ship, the barges are again lashed to each other to prevent damage caused by movement of the carrying ship on the open sea. When the ocean-going ship arrives at its destination, the barges are unlashed from each other, and placed into the water. New barge trains are then formed for river destinations or inland waterway destinations or harbor destinations. Making up the barge trains anew requires that the barges be lashed together again, although, generally, in a different grouping than when the barges were first loaded with their cargoes.
It is obvious that any given barge will be lashed to another barge on frequent occasions. Because of the large number of barges involved in any given operation, sometimes one hundred or more barges being aboard one ship, the lashing and unlashing procedure must be, rapidly, accomplished. Further, because of the weight of the barges, and the potential for damage should a barge lashing fail, the lashing must be extremely sturdy, with an unusually high factor of safety, as well as including safeguards against failure. There is also an essential requirement that the lashing equipment be low in cost, as well as having the other attributes described above. In order that barges achieve their maximum utility, it is necessary that they be capable of being placed anywhere in the barge train. Since each barge has four sides and, therefore has four corners, it is necessary that four sets of lashing equipment be mounted on each barge, one at each corner. Low-cost lashing equipment makes a more-than-customary contribution to the economic feasibility of this transportation system.